Dowell served in the U.S. Army, Medical Corps from 1944 to 1945 and as an assistant to the prosecution in war crimes trials in Manila in 1945–46.
Dowell returned home to the U.S. in 1946 and settled in Louisville, Kentucky for a few years where he was a full-time member of the National Guard.
Dowell moved to New York in 1950, initially finding work as a model for automobile and airline ads and as a typist.
From 1950 to 1953 Dowell was employed as a songwriter and lyricist for the Dumont television show, Once Upon a Tune, which starred Bea Arthur, Elaine Stritch, Alice Ghostley, and Charlotte Rae.
He also worked as David Merrick's protégé and with John La Touche on the abortive Broadway musical version of the 1933 play Ah, Wilderness!
His career included stints as a music critic for The New York Times, as a novelist during the 1920s, and as a photographer for which he never sought nor received payment.
Van Vechten introduced Dowell into his circle of friends which included many celebrities: Isak Dinesen, Langston Hughes, Leontyne Price, Geoffrey Holder, Gloria Vanderbilt, Sidney Lumet, Eileen Herlie, Kim Hunter, Barbra Streisand, Diahann Carroll, Pearl Bailey, Antony Armstrong-Jones, Tallulah Bankhead, Luise Rainer, Laurence Olivier, Gertrude Stein, the Gish sisters, the Duke and Duchess of Windsor, George Kaufman, Noël Coward, and Maurice Sendak, among others.
Dowell, who had written the book, score and lyrics, tried his luck with another theatrical experiment, Eve of the Green Grass.
His theatrical career was also included in his unfinished autobiography, A Dark Book, which was published by The Dalkey Archive Press in June 1993 under the title of A Star-bright Lie.
It was during this period that Dowell enjoyed the critical praise and friendship of such noted authors as Walter Abish, Thom Gunn, John Hawkes, Ann Lauterbach, Gilbert Sorrentino, Maurice Sendak, Edmund White, and Tennessee Williams.
Although there were good times, Dowell could not escape feelings of disillusionment, suicide, or as he put it, "the balcony beckons me."
In the early morning hours on Saturday August 3, 1985, Dowell, reportedly despondent, leapt from his 15th floor apartment balcony overlooking Fifth Avenue.
A large number of famous personalities representing the worlds of dance, art, literature, music, theater, and education toasted their friend and praised his accomplishments as a gifted composer, poet, playwright, novelist, and critic.
[5] A generous donation from an anonymous donor established the Coleman Dowell Series at Dalkey Archive Press.